docs: def broadcast(*sinks_):
      """The |broadcast| decorator creates a |push| object that receives a
      message by ``yield`` and then sends this message on to all the given sinks.
  
      .. |broadcast| replace:: :py:func:`broadcast`
      """
      @push
      def bc():
          sinks = [s() for s in sinks_]
          while True:
              msg = yield
              for s in sinks:
                  s.send(msg)
  
      return bc